A filmmaker, naturalist and environmental activist, and the Executive Director of Earth Overshoot, a nonprofit working to make ecological limits central to all personal and public decision-making through targeted education and advocacy.  Spahr is an expert on sustainability and the intersection of human consumption and population as the primary drivers of environmental destruction. 

Spahr is the producer of the 2019 documentary, 8 Billion Angels, which establishes the fact that the environmental crises the planet is experiencing are far greater than just the symptom of climate change. The film unflinchingly shows that too many people consuming too many resources and emitting too many wastes are having profound impacts on our planet, and that if we are to address our Human Impact Crisis honestly, we can achieve real sustainability marked by tremendous human well being. 

Spahr is a graduate of the University of Pennsylvania College of Arts & Sciences and The Fels Center of Government. 

He had a 25-year career in the insurance, investment and real estate industries and is a former board member of the Long & Foster Companies as well as their philanthropic arm. A sought after speaker. He has presented at numerous conferences and forums, spoken on radio and podcasts, and is a contributor to environmental publications and blogs.